Possible to run an Express in N, and join another N Express broadcasting G?

Question

I hope my title to this explained what I am trying to find out. I have two Airport Express N's that I want to connect to my existing router (Cradlepoint CTR500). One Express will be connected over Ethernet to the router, which is creating the WiFi network, while the second Express in my bedroom is "Joining" my existing WiFi. This is how I have things setup currently.
My entire network is N except for one laptop. When that laptop connects, since it is G, the network goes down to G level from N.
Is there a way to have that one G laptop only connect to one of the WiFi Express routers, say, the bedroom, that is broadcasting at G level, so N users only connect to the other Express broadcasting at N? I don't have a switch to run the second Express as an access point broadcasting at G unfortunately. That might solve my issue here. So in the meantime, I want to find out if I can have that second Express still Join my existing network on N, and then broadcast on G? Or rather instead of Joining, have it Extend my network, but broadcast G instead of N?
Of course, all of this could be solved by just getting a WiFi N USB adapter for our older Powerbook! Or getting a switch in place and running that second bedroom as a G access point.

Answer 1

I don't see how this could work the way you want. One AXn would have to run in b/g/n mode, the 2nd would join the 1st in g-only mode, and the 2nd would cause the 1st to drop to g.
Of course, all of this could be solved by just getting a WiFi N USB adapter for our older Powerbook!
Yes.
Or getting a switch in place and running that second bedroom as a G access point.
You'd want a router -- not a switch. See http://discussions.apple.com/thread.jspa?threadID=1777702&tstart=50